Ask about Yankees reliever David Robertson and you will hear terms like “natural cut” and “long, loose extension” and “fastballs that have late life,” and you realize these are words that have been used for more than a decade to describe Mariano Rivera.

“There are a lot of similarities there in how they throw their fastballs,” Russell Martin said.

Robertson does not have Rivera’s precision or longevity, but in 2011 he has created a season that would fit rather seamlessly next to anything the greatest closer of all-time has produced. Robertson has pitched so well, in fact — with poise and dominance — that you wonder if we are watching Rivera’s heir apparent, a notion the 26-year-old dispatches more easily even than hitters.

“Maybe that can happen a few years down the road,” Robertson said. “But I don’t have to worry about that. Mo’s not leaving. It would be cool to do [to be the closer]. But we have No. 42 and he ain’t leaving.”

In the present, Robertson is going to be asked to be Rivera, circa 1996 — a dominant set-up man who can be pivotal to a championship. Because what distinguishes Rivera, what separates him beyond the designation of best closer ever, is that he arguably is the greatest postseason pitcher in history.

Robertson, who had big moments during the 2009 championship run, wilted in the ALCS last year, collapsed completely in a way Rivera never has in the playoffs. So his next step in this breakout year will be to demonstrate October grace.

Bullpens always are valuable in the 3-2 world of postseason baseball. But when it comes to the 2011 Yankees, well, you know the story. The discussion about the inadequacy of the Yankees’ rotation behind CC Sabathia began last winter, carried through spring training and still is ongoing. So the pen, in general, is going to be in play for the Yankees, and Robertson, in specific, is going to be asked to generate a lot of big outs.

And there also is this: Rivera is 41 now. He remains a genius, still a master of controlling the big moment. But the saves seem to come a little harder these days; the worry about his durability is a drop more palpable around the team. One of the secrets to the Yankees’ success over the years is Rivera could serve as his own setup man in October — pitch the eighth and hand the ball to himself in the ninth.

Rivera has recorded more than three outs in 58 of his

94 playoff appearances (61.7 percent), including half (6 of 12) as recently as the 2009 title season. He is an extreme gamer, which means he will push to do more of the same in 2011. Can he physically handle it? Or, perhaps more relevant, can Robertson handle the eighth as he has this year to make the discussion irrelevant?

“I feel like I am going to see some big situations,” Robertson said.

He could not consider yesterday’s outing preparation since it felt like the polar opposite of playoff baseball: a wet matinee played just hours after the conclusion of a rain-delayed game the previous night against an opponent as dreary as the weather.

To lose to the Orioles, the Yankees pretty much had to do everything wrong, and did. They started a glorified Triple-A lineup owing to the late conclusion of the previous game. They committed four errors and could have been charged with six or seven. They threw four wild pitches, walked eight, permitted five steals and on offense endured a stretch of 0-for-13 with men on base. Still, it took an unearned run and 11 innings for the Orioles to win 5-4.

The rose in this sewage heap of a Yankees performance was Robertson, who struck out the side in the eighth. He has 89 strikeouts in 591⁄3 innings, which is 13.73 per nine innings — by far the best in Yankees history (minimum 50 innings) and 11th best all-time. If he maintains his 1.23 ERA, it would be the best in Yankees history (minimum 50 innings).

Robertson, after a fit of early wildness, has found greater mastery of a cutter that Martin said, “is hard to explain because it has such good rotation it just explodes in the end.” He took the opportunity created by injuries to Rafael Soriano and Joba Chamberlain to assume the eighth inning, to get into a conversation about being Rivera’s heir.

The big hurdle lies ahead, however. Like the Yankees’ closer, Robertson has to show the ability to be Mo-mentous in October.